CN1288489C - Film transistor, TFT substrate and LCD - Google Patents
Film transistor, TFT substrate and LCD Download PDFInfo
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- CN1288489C CN1288489C CNB2003101248379A CN200310124837A CN1288489C CN 1288489 C CN1288489 C CN 1288489C CN B2003101248379 A CNB2003101248379 A CN B2003101248379A CN 200310124837 A CN200310124837 A CN 200310124837A CN 1288489 C CN1288489 C CN 1288489C
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- optical screen
- screen film
- active layer
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- tft
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Images
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers
- H01L27/12—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being other than a semiconductor body, e.g. an insulating body
- H01L27/1214—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being other than a semiconductor body, e.g. an insulating body comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
- H01L27/1218—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being other than a semiconductor body, e.g. an insulating body comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs with a particular composition or structure of the substrate
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/76—Unipolar devices, e.g. field effect transistors
- H01L29/772—Field effect transistors
- H01L29/78—Field effect transistors with field effect produced by an insulated gate
- H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
- H01L29/78606—Thin film transistors, i.e. transistors with a channel being at least partly a thin film with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device
- H01L29/78618—Thin film transistors, i.e. transistors with a channel being at least partly a thin film with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure
- H01L29/78621—Thin film transistors, i.e. transistors with a channel being at least partly a thin film with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure with LDD structure or an extension or an offset region or characterised by the doping profile
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/76—Unipolar devices, e.g. field effect transistors
- H01L29/772—Field effect transistors
- H01L29/78—Field effect transistors with field effect produced by an insulated gate
- H01L29/786—Thin film transistors, i.e. transistors with a channel being at least partly a thin film
- H01L29/78606—Thin film transistors, i.e. transistors with a channel being at least partly a thin film with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device
- H01L29/78633—Thin film transistors, i.e. transistors with a channel being at least partly a thin film with supplementary region or layer in the thin film or in the insulated bulk substrate supporting it for controlling or increasing the safety of the device with a light shield
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/136—Liquid crystal cells structurally associated with a semi-conducting layer or substrate, e.g. cells forming part of an integrated circuit
- G02F1/1362—Active matrix addressed cells
- G02F1/136209—Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers
- H01L27/12—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being other than a semiconductor body, e.g. an insulating body
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers
- H01L27/12—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being other than a semiconductor body, e.g. an insulating body
- H01L27/1214—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being other than a semiconductor body, e.g. an insulating body comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Ceramic Engineering (AREA)
- Liquid Crystal (AREA)
- Thin Film Transistor (AREA)
- Devices For Indicating Variable Information By Combining Individual Elements (AREA)
Abstract
A thin film transistor is provided including an active layer, in which a source region and drain region are formed, a first light-shielding film shielding a light incident on the active layer, and a second light-shielding film between the active layer and the first shielding film. A carrier concentration of at least surface portion of the second light-shielding film which opposes the active layer is about 10<17>/cm<3 >or less.
Description
Technical field
The present invention relates to film transistor device, LCD and specifically be applicable to film transistor device and reduce the manufacture method of the LCD of film transistor device leakage current.
Background technology
Recent years, as the display of OA (office automation) equipment, LCD is developed.In various LCD, compare with conventional display as the active matrix type liquid crystal display of switch element with thin film transistor (TFT) and to have following advantage: even when number of scanning lines increased, contrast or response speed were also not too low.For this reason, the display of the sophisticated display of OA equipment and high-definition television often uses active matrix type liquid crystal display.Also have, when active matrix type liquid crystal display was used as the light valve of porjection type display, as projector, its advantage was to obtain large screen display easily.When active matrix type liquid crystal display is used as the light valve of porjection type display, LCD is arranged in light source and between the optical system of light source projects light, at this moment, LCD is arranged like this, make light source be positioned at one side of the relative substrate of LCD, and the thin-film semiconductor device array substrate (TFT substrate) that optical system is positioned at LCD on one side.Have from light source incident in the middle of the light of higher brightness, LCD is based on the light intensity of screen message control by the optical system limit.More particularly, LCD switch-actuated thin film transistor (TFT), and control action changes the Emission Factor of each pixel in the electric field of the liquid crystal display layer of each pixel, thus regulate radiative intensity.Light by the LCD emission amplifies and projection by the optical system with equipment such as lens.
Usually, in active matrix type liquid crystal display, semiconductor layer is as amorphous silicon and polysilicon, as the active layer of thin film transistor (TFT).When light projects on this active layer, owing to exciting of light produces leakage current (photoinduction leakage current), so the display performance of LCD degenerates because of the contrast step-down.When active matrix type liquid crystal display is used as the light valve of porjection type display,, take place to become big especially because of the influence of photoinduction leakage current because the light of high brightness projects on the LCD.Also have, in this case, because in LCD, light also has the reflected light of optical system to project on the active layer of thin film transistor (TFT) not only from light source, because of the influence of photoinduction leakage current becomes bigger.In recent years, the miniaturization and the high brightness of projection type display have been obtained progress, and projecting to as the luminance brightness on the LCD of light valve has also increased, and therefore, light leakage current problem becomes even more serious.
A kind of technology that reduces because of the influence of photoinduction leakage current as the patent 11-204587A and the 11-084422A of Japanese publication, has been described with interdicting the back light that projects on the thin film transistor (TFT) and has been reduced the technology of light quantity.Fig. 1 represents the cross section of this general LCD.The pixel parts of this LCD has the first polysilicon membrane 452a, silication film 452b, and second polysilicon membrane 453, dielectric film 454, storehouse is on substrate 451 successively for they, and thin film transistor (TFT) 456 is shaped on it.
In general LCD shown in Figure 1, because the film of storehouse is formed first optical screen film 452 and second optical screen film 453, the light that projects polysilicon layer (active layer of thin film transistor (TFT)) 455 is interdicted.In first optical screen film 452, the light that projects the active layer of thin film transistor (TFT) 456 from the substrate back end is had the very silicification film 452b blocking-up of high light reflection characteristic.Also have, second light shielding layer 453 by polysilicon film constitutes has optical absorption characteristics, absorbs to enter between first optical screen film 452 and the active layer 455, and the light of unsilicided film 452b blocking reduces the light that projects on the active layer 455.
In general LCD shown in Figure 1, the thickness of dielectric film 454 is about 380 nanometers, in this case, in the light that is returned by substrate 451 reflections, be included in the light in the differential seat angle β between limit light ray L11 and the limit light ray L12, as shown in Figure 1, become the light in the grid level electrode lower channel district that directly projects active layer 455.When the light intensity from light source increases,,, also show not enough especially even second polycrystalline film 453 of optical absorption characteristics is arranged to the light shield effect that reflects the light that returns by substrate 451.When light projects the channel region of active layer 455, on thin film transistor (TFT) 456, produce the photoinduction leakage current, make the performance depreciation of LCD.For this reason, when LCD is used as the light valve of porjection type display, need shielding more effectively to project the technology of the light on the thin film transistor active layer 455 especially.
Summary of the invention
The invention provides a kind of thin film transistor (TFT) of using, TFT substrate and the light that projects on the thin film transistor (TFT) channel region by means of minimizing reduce the LCD of thin film transistor (TFT) photoinduction leakage current, and reduce the film sound of optical screen film to thin film transistor active layer.
According to first embodiment of the invention, thin film transistor (TFT) comprises active layer, wherein forms source region and drain region; First light shielding layer, shielding projects the light on the active layer; Second light shielding layer between the active layer and first screened film wherein, is 10 in the carrier concentration facing to the surface portion of second optical screen film of active layer at least
17/ cm
3Or still less.
According to second embodiment of the invention, thin film transistor (TFT) comprises active layer, wherein forms source region and drain region; First optical screen film, shielding projects the light on the active layer; Second optical screen film between the active layer and first screened film, wherein, facing to the electric field intensity of the second optical screen film surface portion of active layer for facing to the surface portion electric field intensity of first light shielding layer 80% or littler, wherein, the carrier concentration facing to the second optical screen film surface portion of active layer is 10
17/ cm
3Or still less.
According to third embodiment of the invention, thin-film transistor substrate comprises light emission substrate, comprises to be deposited on the transistor array that light is launched on-chip a plurality of thin film transistor (TFT)s; Be deposited on first optical screen film between light emission substrate and at least one thin film transistor (TFT); Second optical screen film between first optical screen film and thin film transistor active layer, wherein, the carrier concentration that faces toward the second light shielding layer surface portion of active layer is 10
17/ cm
3Or still less.
Description of drawings
Fig. 1 is illustrated in the cross-sectional structure figure of thin film transistor (TFT) array substrate in the general LCD.
Fig. 2 is near the planimetric map of thin film transistor (TFT) array substrate upper film transistor of first embodiment of the invention.
Fig. 3 is the cross-sectional view of Fig. 2 along A-A ' line.
Fig. 4 (a) to (d) is the sectional view that the expression first embodiment of the invention is made thin film transistor (TFT) array substrate method.
Fig. 5 (a) and (b) be then Fig. 4 (d) makes the sectional view of thin film transistor (TFT) array substrate method.
Fig. 6 (a) and (b) be then Fig. 5 (b) makes the sectional view of thin film transistor (TFT) array substrate method.
Near Fig. 7 (a) and (b) the expression active layer, can be with from optical screen film respectively.
Fig. 8 represents the graph of a relation of total amount of electric charge in the carrier concentration of optical screen film and the screened film current potential.
Fig. 9 is the thin film transistor (TFT) array substrate cross-sectional structure figure of second embodiment of the invention.
Figure 10 (a) and (b) the expression second embodiment of the invention be used for the sectional view of thin film transistor (TFT) array substrate manufacture method.
Figure 11 is the thin film transistor (TFT) array substrate cross-sectional structure figure of third embodiment of the invention.
The thin film transistor (TFT) array substrate cross-sectional structure figure of Figure 12 fourth embodiment of the invention.
The thin film transistor (TFT) array substrate cross-sectional structure figure of Figure 13 fifth embodiment of the invention.
Figure 14 is the thin film transistor (TFT) array substrate cross-sectional structure figure of sixth embodiment of the invention.
Embodiment
Fig. 2 is the thin film transistor (TFT) planimetric map of first embodiment of the invention LCD, and Fig. 3 is the sectional view along A-A ' line among Fig. 2, in Fig. 2 and 3, has represented to be contained in a plurality of thin film transistor (TFT)s in the TFT substrate 32.
As shown in Figure 2, TFT substrate 32 has a plurality of thin film transistor (TFT)s 33 that are arranged to rectangular, each thin film transistor (TFT) 33 form in one group along Y to the parallel data line 28a that extends with along directions X near the infall between the parallel grid level line 26a that extends.Gate line 26a for example, is made by polysilicon film or silicification film, dosed carrier wherein, data line 28a by the aluminium film or similarly material make.The matrix 34 of black is made by chromium film or this class material with light shield characteristic, and is formed on and overlaps in space gate line 26a, data line 28a and thin film transistor (TFT).Pixel area 31 is cut apart by gate line 26a and data line 28a (by black matrix" 34), and pixel capacitors 23 is rectangle basically, and it is made by transparency electrode, as the indium tin oxide on the pixel zone (ITO).
As shown in Figure 3, TFT substrate 32 has substrate 1, ground medium film 2, the first optical screen films 3, the first deielectric-coating 4, the second optical screen films 5, the second deielectric-coating 6, active layer 7, they from bottom in succession storehouse get up.Also have, a gate dielectric film 10 is arranged, grid level electrode 13, the first interlayer dielectric films 14, source electrode 15, drain electrode 16, the second interlayer dielectric films 17, lower curtate electrode 18, electric capacity dielectric film 19, upper electrode 20 on the upper strata of active layer 7.The 3rd interlayer dielectric film 21 flattens film 22 and pixel capacitors 23.
Second optical screen film 5, it has unglazed emission characteristics, is made by amorphous silicon, can absorbing light, and form in the regional 5a and the regional 5b corresponding to thin film transistor (TFT) corresponding to grid level line 26a, as shown in Figure 2.Second optical screen film 5 on the low layer limit corresponding to thin film transistor region, forms in the zone of overlapping active layer 7X direction, or is slightly wider than the zone of active layer 7.Also have, second optical screen film 5 is changed to 10 facing to the carrier concentration of the surface portion of active layer 7
17/ cm
3Or still less.Second optical screen film 5 is arranged to cover first optical screen film 3 in the space, has near area identical with first optical screen film 3.In addition, second optical screen film can be from littler than the area of first optical screen film 3.Second deielectric-coating 6 is made by Si oxide, and forms between optical screen film 5 and the active layer 7, and its film thickness is about 150 nanometers.
On active layer, grid level deielectric-coating 10 is arranged, it is made by Si oxide.On grid level deielectric-coating 10, grid level electrode 13 is arranged, it is made by the tungsten silication, near active layer 7X direction center.Between the channel region 27 of source region 8 and the positive F of grid level electrode, a low concentration regions of carriers 11 is arranged, between leaking area 9 and channel region 27, another low concentration current-carrying subarea 12 is arranged.Channel region 27 covers the lead 26b that protrudes from grid level line 26a and goes up (Fig. 2), and grid level electrode 13 and grid level line 26a interconnect by contactor.First interlayer dielectric film 14 is arranged at the top at grid level deielectric-coating 10 and grid level electrode 13, and it is made by siliceous oxide.
The second interlayer dielectric layer 17 is made by silicon nitride, and forms in the first interlayer dielectric film 14, the top of source electrode 15 and drain electrode 16.At second interlayer dielectric film, 17 tops, the low electrode 18 that is made of chromium and microcrystal silicon lamination is arranged.At the top of low electrode 18, deielectric-coating 19 is arranged, as electric capacity, it is made by silicon nitride.At the top of deielectric-coating 19 top electrode 20 is arranged, it by titanium, contain aluminium silicon and microcrystal silicon layer is pressed into.Top electrode 20 is connected with drain electrode 16 by the second data line 28b (Fig. 2).Top electrode 20 and low electrode 18 toward each other, deielectric-coating 19 constitutes the pixel storage capacitors between wherein.At the top of top electrode 20 the 3rd interlayer dielectric film 21 is arranged, it is made by silicon nitride.
Fig. 4 (a) is to (d), Fig. 5 (a) and (d), and the Fig. 6 (a) and (b) manufacture method of expression TFT substrate 32.At first, by means of the CVD method, ground medium film 2 forms on the whole surface of the substrate 1 that glass substrate by high strain-point and so on makes, and thickness is about 300 nanometers, and on ground medium film 2.First optical screen film 3, it is the metal silicide film that very emergency light reflex characteristic is arranged, and makes thickness with sputtering method (Fig. 4 (a)) and is about 1 75 nanometers.Then, stay photoresist, in this district, form active layer 7 or in big slightly zone, this district, form active layer 7, and first optical screen film, 3 usefulness dry corrosion methods are selectively removed (Fig. 4 (b)) with photoetching process in certain district.
Use the CVD method, dielectric film 4 is configured as about 150 nanometers of thickness, and at its top, with CVD method second optical screen film 5 that is shaped, its thickness is about 60 nanometers.Then, use the ion doping method, ion implantation, or the vapour phase method of batching, charge carrier is injected into second optical screen film 5, in addition, as Fig. 4 (b), the zone that forms active layer 7 stays photoresist, or stays photoresist with photoetching process in the district wideer than this district, and second optical screen film is removed selectively with dry corrosion method (Fig. 4 (c)).When charge carrier injected, in the charge carrier section of the second optical screen film vertical direction, charge carrier was such state, and the surface portion carrier concentration that promptly faces toward second optical screen film 5 of active layer 7 is about 10
17/ cm
3Or still less, and in this injection period, maximum carrier concentration is near the concentration of active layer 7 facing to the surface of dielectric film 6.
Use the CVD method, dielectric film 6 is configured as about 150 nanometers of thickness, and active layer 7 forming thicknesses are about 60 nanometers, and grid level deielectric-coating 10a is about 10 nanometers with CVD method forming thickness.After this, charge carrier injects active layer 7 with such state, promptly makes a year ion concentration be about 10 with ion doping method or ion implantation
15/ cm
3Then, in order to improve active layer 7 crystal mass, active layer 7 usefulness excimer lasers are annealed, thereby improve the quality of active layer 7 crystal, and form the thin film transistor (TFT) with fabulous characteristic.
Then, the zone that forms active layer 7 in photoetching process stays photoresist, in the zone of non-formation active layer 7, removes photoresist with the dry corrosion method.After this, photoresist is stayed any other area of non-formation source region 8 and leaking area 9 with photoetching process, and uses the ion doping method, or ion implantation injection charge carrier, and making carrier concentration is 5 * 10 to source region 8 and leaking area 9 respectively
20/ cm
3After charge carrier injects, grid level deielectric-coating 10b, with CVD method (Fig. 4 (d)), being shaped is about the thickness of 90 nanometers.
In source region 8 with corresponding to any zone between the zone 27 of grid level electrode 13, and leaking area 9 and corresponding to the zone between the zone 27 of grid level electrode 13, stay photoresist with photoetching process, and use the ion doping method, or ion implantation, inject with low carrier concentration, form about 10
17/ cm
3Low concentration current-carrying subarea 11,12 (Fig. 5 (a)).After this, the charge carrier that is injected into activates with the hydrogenation of CVD equipment.
Then, constitute the method for common LCD, form grid level electrode 13, the first interlayer dielectric films 14, source electrode 15 and drain electrode 16 as the thin film transistor device array substrate.When forming source electrode 15 and drain electrode 16, in LCD, for any peripheral circuit (not shown) of non-thin film transistor device array substrate 32 pixel regions, first optical screen film 3 and second optical screen film 5 will be distinguished electrical connection with it.After this, form second interlayer dielectric film 17 (Fig. 5 (b)).
Use the CVD method, form crystal silicon film, its thickness is about 100 nanometers, forms the chromium film with sputtering method, and its thickness is 140 nanometers, with their lamination formation low electrode 18.Use photoetching process, photoresist is stayed the back that forms low electrode 18 zones, form low electrode 18 with the dry corrosion method.Then, form deielectric-coating 19 with the CVD method, its thickness is about 100 nanometers, and by forming contact hole, top electrode 20 is linked electric leakage electrode 16.After this, formation contains aluminium silicon by titanium and the prosperous silicon layer of knot is pressed the electrode that constitutes storage capacitors, and its thickness is about 550 nanometers, and with photoetching process photoresist is stayed the zone that forms top electrode 20, uses dry corrosion method (Fig. 6 (a)) formation top electrode again.
Use the CVD method, form the 3rd interlayer dielectric film 21, its thickness is about 400 nanometers, forms with rotary spraying then and flattens film, and its thickness is about rice in 1690.Form contact hole on the flattening film, be used for forming pixel capacitors 23 (Fig. 6 (b)) after the top electrode 20 of pixel capacitors 23 connection storage capacitors with sputtering method, its thickness is about 40 nanometers.With the manufacture process of foregoing description, obtain the TFT substrate 32 of cross section structure shown in Figure 3.
In the present embodiment, between the substrate 1 and active layer 7 of TFT substrate 32, be furnished with first optical screen film 3 made by the metal silicide of high-conductivity and second optical screen film 5 of unglazed emission characteristics.Distance between second optical screen film 5 and the active layer 7 (film thickness of deielectric-coating 6) can be put and is about 150 nanometers.Therefore, compare (wherein the distance between optical screen film and the active layer is changed to 380 nanometers) with general LCD shown in Figure 1, it has improved light shielding effect because of having reduced the light quantity that projects on the active layer 7, and further blocks the light (back light) that returns thin film transistor (TFT) 33 (Fig. 3) from substrate 1 end effectively.
The thin film transistor (TFT) 33 of formation TFT substrate 32 has the high light shield effect to active layer 7, and the influence of rarer photoinduction electric current.Therefore, the switching characteristic of thin film transistor (TFT) is improved, and becomes to control pixel capacitors 23 satisfactorily.In the LCD that comprises TFT substrate 32, even when as the light valve in the porjection type display (wherein high-luminance light is as light source), can realize high brightness and high-contrast.
As shown in Figure 3, in the present embodiment, because the distance between the active layer 7 and second optical screen film 5 is than the weak point of generalized case, its angular difference is littler than limit light ray L11 shown in Figure 1 and the differential seat angle β between the L12.Therefore, compare, project the channel region 27 of active layer 7 and the light quantity in low concentration current-carrying subarea 11,12 and reduce,, thereby can improve the performance of LCD owing to the performance depreciations such as contrast reduction that the photoinduction leakage current causes can be avoided with general LCD.
On the other hand, under regular situation, distance between the second light shield curtain 453 and active layer 455 is provided with more in short-term, the current potential that acts between first optical screen film 452 and second optical screen film 453 causes second optical screen film 453 to act on the thin film transistor (TFT) as back grid level, because the back grid level of thin film transistor (TFT) 33 has been brought leakage current.This is owing to second optical screen film 453 is conductions, when second optical screen film 453 during more near active layer 455, active layer is just had the influence (Fig. 1) of electricity.
In the present embodiment, make facing to the carrier concentration in the surface portion of second light shielding layer 5 of active layer 7 and reduce, thereby owing to act on the electric field that the current potential of first optical screen film 3 causes and discharged by optical screen film 5, the film that has reduced thin film transistor (TFT) 33 rings.In view of the above, though when second optical screen film 5 and active layer 7 mutually near the time, the influence of the leakage current that the performance of LCD can not cause because of back grid level degenerates.
Fig. 7 (e) and (b) be illustrated respectively in this embodiment and in conventional structure, near the active layer from the energy band of optical screen film.Fig. 8 represents the mutual relationship between the quantity of electric charge in optical screen film carrier concentration and the optical screen film current potential.Fig. 7 (a) and (b) be illustrated respectively in the energy level state between first screened film 3 and grid level electrode 13 (being shown in Fig. 3) in this embodiment and the conventional structure.In Fig. 7 (a), the carrier concentration of the second optical screen film 5A is changed to 10
17/ cm
3Low value.In Fig. 7 (b), the carrier concentration of the second optical screen film 5B is changed to 10
22/ cm
3The high value.
When being low value, the carrier concentration of the second optical screen film 5A (shows) as Fig. 7 (a), the current potential V that acts on first optical screen film 3 causes the bending that can be with among the second optical screen film 5A, makes at the second optical screen film 5A and produce potential difference (PD) Δ V (potential loss) between first optical screen film, 3 ends and active layer 7 ends.On the other hand, when the carrier concentration of the second optical screen film 5B when being high (showing) as Fig. 7 (b), in the second optical screen film 5B, there is not the bending that to be with, but the current potential of the second optical screen film 5B becomes the current potential V that equals first optical screen film 3, and second optical screen film does not have potential difference (PD) between the current potential of first optical screen film, 3 ends and active layer 7 ends.In view of the above, if the potential difference (PD) between first optical screen film 3 and the grid level electrode 13 is a constant, then the band curvature in the active layer 7 of Fig. 7 (b) is greater than the band curvature among Fig. 7 (a).
Comparison diagram 7 (a) and Fig. 7 (b), in Fig. 7 (a), the second optical screen film 5A helps to discharge the electric field of first optical screen film 3, and among Fig. 7 (b), the second optical screen film 5B does not help to discharge the electric field of first optical screen film 3.The carrier concentration of second optical screen film 5 be Fig. 7 (a) than low value the time, the crooked little amount that can be with among the bend ratio Fig. 7 (b) that can be with in the active layer 7 corresponding to potential difference (PD) Δ V among the second optical screen film 5A.
The carrier concentration 5 of second optical screen film and the relation that occurs between the interior potential difference (PD) Δ V of second optical screen film are shown in Fig. 8.As shown in Figure 8, low more facing to the surface portion carrier concentration of second optical screen film 5 of active layer 7, the potential difference (PD) in second optical screen film 5 is big more.When the current potential (for example) of 5V acts on first optical screen film 3, be changed to 10 if face toward the surface portion carrier concentration of second optical screen film 5 of active layer 7
17/ cm
3(shown in same figure), potential difference (PD) Δ V becomes 1V so, and the electric field energy of first optical screen film 3 is released 20%.Therefore, be 10 by means of the surface portion carrier concentration of putting facing to second optical screen film 5 of active layer 7
17/ cm
3Or still less, then since first optical screen film 3 discharge 20% current potential or mostly be possible, and since the current potential of first optical screen film 3 to discharge electric field effects very big.
In example of the present invention, be equal to or less than facing to 80% of the first optical screen film surface portion because be changed to facing to the second optical screen film surface portion electric field intensity of the active layer of thin film transistor (TFT), then the electric field owing to first optical screen film (it influences the active layer of thin film transistor (TFT)) can be discharged by second optical screen film, in view of the above, even when second optical screen film during near the active layer of thin film transistor (TFT), keep because the low current leakage of back grid level effect is possible, and the switching characteristic of thin film transistor (TFT) becomes more excellent.
In the present embodiment, the thickness of second deielectric-coating 6 is put and is about 150 nanometers, puts facing to the surface portion carrier concentration of second optical screen film 5 of active layer 7 to be about 10
17/ cm
3, but be lower than 150 nanometers when the thickness of second deielectric-coating 6, and the distance between second optical screen film 5 and the active layer 7 is when shortening further, can be changed to facing to the surface portion carrier concentration of second optical screen film 5 of active layer 7 and be lower than 10
17/ cm
3In this case, the surface portion carrier concentration that faces toward second optical screen film 5 of active layer is put lowlyer, and the potential difference (PD) Δ V that occurs in second optical screen film 5 becomes bigger.Make the release work of second optical screen film 5 become stronger.In view of the above, even when the thickness of second deielectric-coating 6 is done thinlyyer (in order to strengthen the light shield effect of second optical screen film 5), keep because the low current leakage of back grid level effect is possible.The surface portion carrier concentration that faces toward second optical screen film 5 of active layer can be set to like this, makes second optical screen film 5 potential difference (PD) between first optical screen film, 3 ends and active layer 7 ends surpass the current potential 20% that acts on first optical screen film 3.
When the thickness of putting second deielectric-coating 6 (distance between second optical screen film 5 and the active layer 7) is 350 nanometers or when thicker, the light that arrives active layer 7 has increased, the photoinduction leakage current becomes outstanding.Also have, when the thickness of putting second deielectric-coating 6 is 100 nanometers or more hour, second optical screen film, 5 films ring active layer 7, because the leakage current of back grid level becomes outstanding.Therefore, the thickness of second deielectric-coating 6 can be changed to from about 100 nanometers to about 350 nanometers.The thickness of second deielectric-coating 6 is changed to 100 nanometer to 350 nanometers, thereby it may strengthen the light shield effect, avoids photoinduction leakage current and because the leakage current of back grid level.Aspect the light shield effect, the thickness of second deielectric-coating 6 can be between 150 nanometer to 250 nanometers.When the thickness of second optical screen film 5 is changed to 50 nanometers or still less the time, second optical screen film 5 does not have non-smooth emission characteristics, when it is changed to 200 nanometers or when bigger, second optical screen film, 5 films ring active layer 7, because the leakage current of back grid level becomes outstanding.Enhancing light shield effect is avoided the light leakage current and because the leakage current of back grid level effect is possible.
Fig. 9 is the sectional view of second embodiment of the invention LCD TFT substrate 32A.This routine TFT substrate 32A has the planar structure that is similar to Fig. 2, and the sectional view of Fig. 9 is corresponding to the cross section of Fig. 2 along A-A ' line.This example is different from first embodiment, and first optical screen film 3 and second optical screen film 5 are mutual storehouses and do not have deielectric-coating 4 (Fig. 3).TFT substrate 32A has substrate 1, ground medium film 2, the first optical screen film 3, the second optical screen films, 5, the second deielectric-coating 6 and active layers 7, and they are order storehouse from low to high according to this.
Figure 10 (a) and (b) the expression second embodiment of the invention make the method for TFT substrate 32A.At first, use the CVD method, the thick ground medium film 2 of about 300 about rice is made in the whole surface of the substrate of making by high stress point glass and so on 1, on ground medium film 2, use sputtering method, make the tungsten silicification film of being made by the metal silication with reflective character, its thickness is about 175 nanometers, as first optical screen film 3.Further, on the top of this film, with CVD method (Figure 10 (a)), storehouse second optical screen film 5, its thickness is about 60 nanometers.
Then, photoresist is stayed the zone that will make active layer 7, or stay the zone wideer slightly, and second optical screen film 5 is removed with dry corrosion method (Figure 10 (b)) than above-mentioned district with photoetching process.Then, use with Fig. 4 (d) to the identical method of Fig. 6 (b), obtain the TFT substrate 32A that this example has cross section shown in Figure 9.
In the present embodiment, because the storehouse of first optical screen film 3 and second optical screen film 5, the centre does not form first deielectric-coating 4, thereby the process that forms first deielectric-coating 4 has been saved, even in this case, identical with first embodiment, for the light shield effect height of active layer 7, even and comprise in the LCD of this routine TFT substrate 32A, also realized high brightness and high-contrast.Also have, because first optical screen film 3 and second optical screen film 5 are direct storehouse, the current potential of first optical screen film 3 and second optical screen film 5 becomes and is equal to each other.Unlike first example, it does not need charge carrier is injected second optical screen film 5, but has only first optical screen film 3 to be electrically connected with the peripheral circuit (not shown).In view of the above, manufacture method is simpler than first example, thereby, can shorten the manufacturing cycle, and improve the flow that LCD is made.
Figure 11 represents the sectional view of the TFT substrate 32B of third embodiment of the invention LCD.This routine TFT substrate 32B has the planar structure identical with Fig. 2, and cross section shown in Figure 11 is corresponding to the cross section of Fig. 2 A-A ' along the line.This example is different from first example, and it does not provide storage capacitors as shown in Figure 3.
In this example, different with first example, TFT substrate 32B does not have storage capacitors.Even in this case, as the situation of first example, the light shield effect of first optical screen film 3 and 5 pairs of active layers 7 of second optical screen film has increased, even and in the LCD that comprises this routine TFT substrate 32B, also can realize high brightness and high-contrast.
Figure 12 is the TFT substrate 32C cross section structure of fourth embodiment of the invention LCD.This routine TFT substrate 32C has the planar structure identical with Fig. 2, and Figure 12 is the cross section corresponding to A-A ' along the line among Fig. 2.This example is different from second example, and it does not provide storage capacitors shown in Figure 9.
At the upper strata of active layer 7 end, TFT substrate 32C has done grid level deielectric-coating 10, grid level electrode 13, the first interlayer dielectric films 14, source electrode 15, drain electrode 16, the second interlayer dielectric films 17 and pixel capacitors 23.This TFT substrate obtains as follows: as Figure 10 (a) and (b) and Fig. 4 (d) to 5 (b), up to forming second interlayer film 17; After this, do not produce storage capacitors, form second interlayer dielectric film 17, and contact hole is arranged; Pixel capacitors 23 links to each other with drain electrode 16, obtains TFT substrate 32C like this.
In this example, unlike second example, the TFT substrate does not have storage capacitors, even in this case, situation as first example, the light shield effect height of first optical screen film 3 and 5 pairs of active layers 7 of second optical screen film, even and in the LCD that comprises this routine TFT substrate 32C, also can realize high brightness and high-contrast.Also have,, can improve the flow that LCD is made as the situation of second example.
Figure 13 represents the cross section structure of the TFT substrate 32D of fifth embodiment of the invention.Here, Figure 13 represents to form the method corresponding to first optical screen film 7 of first optical screen film 7 among Fig. 3.Also have, TFT substrate 32D is near pixel region 31 shown in Figure 2, and leaking area has PEL matrix district 103, wherein forms thin film transistor (TFT), is used for controlling the pixel and the excitation region 104 that are connected with pixel capacitors, wherein forms the peripheral circuit as the exciting circuit.
Next step, deielectric-coating 106 is made rice in the thickness 150, and on deielectric-coating 106, makes active layer 107.Active layer 107 is made by noncrystalline silicon fiml, is made in PEL matrix district 103 and leaking area 104.Thin film transistor (TFT) in PEL matrix district 103 is as the transistor of control pixel capacitors, and the thin film transistor (TFT) in excitation region 104 is as the transistor that constitutes this class of exciting circuit.The active layer 107 that is made in PEL matrix district 103 and excitation region 104 is by the excimer laser annealing.
In the process that forms active layer 107, because the low layer end of active layer 107 in PEL matrix district 103, be formed with optical screen film 105, when the laser radiation of active layer (it is non-crystal silicon film) during with laser annealing, pass to substrate 101 ends by the heat that laser produces by the thermal conductance characteristic of optical screen film 105, therefore, active layer 107 forms with the polysilicon film of low crystalline quality (that is low mobility), in view of the above, in the thin film transistor (TFT) that forms in PEL matrix district 103, the photoinduction electric current further reduces.On the other hand, the active layer 107 in excitation region 104 is as the active layer in PEL matrix district 103, by laser annealing, still, because the low layer end of the active layer 107 in excitation region 104, do not form optical screen film 105, thereby the heat that does not have too many laser to produce passes row substrate 101 ends.Therefore, active layer 107 forms with the polysilicon film of high crystalline quality (that is high mobility).In view of the above, the switching characteristic that is formed on the thin film transistor (TFT) in the excitation region 104 improves.
In this example, in PEL matrix district 103, constitute the low layer end of the active layer 107 of thin film transistor (TFT)), be furnished with optical screen film 105, it has thermal conductivity, but constitutes the low layer end of the active layer 107 of thin film transistor (TFT) in excitation region 104, does not have optical screen film.In this case, when the active layer 107 in these two districts during by laser annealing, with whether have the optical screen film 105 of thermal conductivity relevant, promptly opinion active layer 107 is in kind made, and the characteristic of thin film transistor (TFT) dissimilates in the characteristic of the thin film transistor (TFT) in the PEL matrix district 103 and the excitation region 104.
Because not being both of above-mentioned tft characteristics because the thermal conductivity of optical screen film 105 causes, thereby, as long as there is the film of thermal conductivity just can obtain the difference of above-mentioned tft characteristics as optical screen film (no matter structure of optical screen film) on the active layer 107 low layer ends that in PEL matrix district 103, form.When the thickness (distance between optical screen film 105 and the active layer 107) of deielectric-coating 106 is changed to 350 nanometers or when bigger, heat treated heat can not passed to the optical screen film 105 of enough thermal conductivity during laser annealing.The characteristic of active layer 107 can not change because of whether optical screen film 105 is arranged on the low layer end.Also have, when the thickness of deielectric-coating 106 is changed to 100 nanometers or more hour, between the active layer 107 that active layer 107 and the low layer end of the relevant screened film 105 of low layer end do not have optical screen film 105, owing to laser annealing thermal treatment causes the variation of characteristic too big.In addition, can not obtain good especially thin film transistor (TFT) on state characteristic, therefore, the thickness of deielectric-coating 106 can place between about 100 nanometers and the about 350 interior rice, as the situation of second deielectric-coating 6 in first example.
Figure 14 is the sectional view of sixth embodiment of the invention LCD.According to the thin-film transistor substrate 32 of first example, the substrate 41 and the liquid crystal layer 40 that face toward dispose as Figure 14.Thin-film transistor substrate can be with arbitrary thin-film transistor substrate of first to the 5th example.
In above-mentioned first to fourth example, show the example of making first optical screen film 3 with the tungsten silication, but replaced tungsten, available tantalum (Ta), titanium (Ti), the metalloid of chromium (Cr) and molybdenum, and these metals do not need high temperature of fusion.Also have, as the optical screen film in the 5th example 105, as first to fourth example, also available tungsten silicification film, and replace tungsten, available tantalum (Ta), titanium (Ti), chromium (Cr), molybdenum (Mo) etc.
In above-mentioned first to fourth example, shown the example of second optical screen film 5, amorphous silicon with optical absorption characteristics can be used as second optical screen film, but, use semiconductive thin film, for example microcrystal silicon (μ c-Si), noncrystalline Si-x Gex system, many germanium (poly-Ge), noncrystalline germanium (a-Ge) and many Si-xGex system all can obtain and the identical effect of above-mentioned each example.Also have, in above-mentioned first to fourth example, shown the example as grid level electrode 13, the tungsten silicification film can be used as grid level electrode 13, but tantalum (Ta), titanium (Ti), chromium (Cr), molybdenum (Mo), aluminium first optical screen film etc. also can use.
In above-mentioned first to fourth example, shown the example that the CVD method is used to form second optical screen film, 5 grades, but sputtering method, plasma CVD methods etc. also can use.Also have, the active layer of the deielectric-coating that on the whole surface of substrate, forms, optical screen film, thin film transistor (TFT), the thickness of grid level deielectric-coating etc. has all provided an example, and makes appropriate change according to purpose.Also have, inject at second optical screen film, 5 charge carriers, second optical screen film that obtains low carrier concentration in the semiconductive thin film with conduction type charge carrier by means of the conduction type charge carrier that injects and this charge carrier is reverse also is possible.
The explanation of each example of front can make the insider make or use the present invention.In addition, all very easy various remodeling of understanding these examples of insider, General Principle given here and specific example need not innovation and just can be used for other example.Therefore, the present invention is by being limited to the embodiments described herein, and in the wide region that is applicable to that claim and equivalence thereof determine.
Claims (19)
1. thin film transistor (TFT) comprises:
Active layer wherein forms source region and leaking area;
First optical screen film, shielding projects the light of active layer;
Second optical screen film, it is arranged between the active layer and first optical screen film, wherein,
At least the carrier concentration that faces toward the second optical screen film surface portion of active layer is 10
17/ cm
3Or still less.
2. thin film transistor (TFT) according to claim 1 is characterized in that the distance between second optical screen film and the active layer is between 100 nanometer to 350 nanometers.
3. thin film transistor (TFT) according to claim 1 is characterized in that active layer has the low concentration current-carrying subarea between source region and channel region, wherein,
Between leaking area and channel region, said low concentration current-carrying subarea has the conduction type identical with source region and leaking area, and its impurity concentration low than source region and leaking area;
Said second optical screen film has part overlapping with channel region and plane, low concentration current-carrying subarea.
4. thin film transistor (TFT) according to claim 1 is characterized in that second optical screen film has absorbing properties.
5. thin film transistor (TFT) according to claim 1 is characterized in that also comprising the deielectric-coating that is arranged between first optical screen film and second optical screen film.
6. thin film transistor (TFT) according to claim 1 is characterized in that second optical screen film is formed on first optical screen film.
7. thin film transistor (TFT) comprises:
Active layer wherein forms source region and leaking area;
First optical screen film, shielding projects the light on the active layer;
Second optical screen film, it is arranged between the active layer and first optical screen film,
Wherein, facing to the electric field intensity of the surface portion of second optical screen film of active layer be facing to the electric field intensity of the surface portion of described second optical screen film of first optical screen film 80% or littler, wherein, the carrier concentration facing to the second optical screen film surface portion of active layer is 10
17/ cm
3Or still less.
8. thin film transistor (TFT) according to claim 7 is characterized in that the distance between second optical screen film and the active layer is 100 nanometer to 350 nanometers.
9. thin film transistor (TFT) comprises:
Active layer wherein forms source region and leaking area;
First optical screen film, shielding projects the light of active layer;
Second optical screen film, it is arranged between the active layer and first optical screen film,
Wherein, second optical screen film is made by the semiconducting insulation film, and wherein, the carrier concentration of second optical screen film is 10
17/ cm
3Or still less.
10. thin film transistor (TFT) comprises:
Active layer wherein forms source region and leaking area;
First optical screen film, shielding projects the light of active layer;
Second optical screen film, it is arranged between the active layer and first optical screen film,
Wherein, second optical screen film is by selecting to make in following one group of material: amorphous silicon, and silicon metal, noncrystalline SiGe, many germanium, noncrystalline germanium, many SiGes and their combination in any, wherein, the carrier concentration of second optical screen film is 10
17/ cm
3Or still less.
11. a thin-film transistor substrate comprises
Light emission substrate;
Transistor array comprises that a plurality of light that are arranged in launch on-chip thin film transistor (TFT);
First optical screen film, it is arranged between light emission substrate and at least one thin film transistor (TFT);
Second optical screen film, it is arranged between the active layer of first optical screen film and thin film transistor (TFT),
Wherein, the carrier concentration facing to the surface portion of second optical screen film of active layer is 10
17/ cm
3Or still less.
12. thin-film transistor substrate according to claim 11 is characterized in that also comprising the pixel capacitors corresponding to each thin film transistor (TFT),
Wherein, each pixel capacitors is by the thin film transistor (TFT) excitation of pixel capacitors correspondence.
13. thin-film transistor substrate according to claim 12 is characterized in that the deielectric-coating between capacitance electrode is parallel-connected to pixel capacitors.
14. thin-film transistor substrate according to claim 13 is characterized in that also comprising another thin film transistor (TFT), it neither comprises first optical screen film, does not also comprise second optical screen film.
15. thin-film transistor substrate according to claim 11, it is characterized in that electric field intensity facing to the surface portion of second optical screen film of active layer be facing to the electric field intensity on the surface of described second optical screen film of first optical screen film 80% or still less.
16. thin-film transistor substrate according to claim 11 is characterized in that second optical screen film is by selecting to make in following one group of material: amorphous silicon, silicon metal, noncrystalline SiGe, many germanium, noncrystalline germanium, many SiGes, and combination in any.
17. a LCD comprises:
The described thin-film transistor substrate of claim 11;
The relative substrate of arranging on the thin-film transistor substrate opposite;
The liquid crystal display layer of between thin-film transistor substrate and relative substrate, arranging.
18. a thin film transistor (TFT) autofrettage comprises:
Substrate is provided;
On above-mentioned substrate, form the ground medium film;
Form first optical screen film;
On first optical screen film, form second optical screen film;
Charge carrier is doped to second optical screen film, and making the carrier concentration of the surface portion of second optical screen film that faces toward active layer at least is 10
17/ cm
3Or still less;
On second optical screen film, form deielectric-coating;
On above-mentioned deielectric-coating, be formed for the active layer of thin film transistor (TFT).
19. thin film transistor (TFT) autofrettage according to claim 18 is characterized in that deielectric-coating is after forming first optical screen film and making before formation second optical screen film on first optical screen film.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003024473 | 2003-01-31 | ||
| JP2003024473A JP4423659B2 (en) | 2003-01-31 | 2003-01-31 | Thin film transistor, TFT substrate, and liquid crystal display device |
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| Publication Number | Publication Date |
|---|---|
| CN1519631A CN1519631A (en) | 2004-08-11 |
| CN1288489C true CN1288489C (en) | 2006-12-06 |
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| CNB2003101248379A Expired - Fee Related CN1288489C (en) | 2003-01-31 | 2003-12-31 | Film transistor, TFT substrate and LCD |
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| US (1) | US7105905B2 (en) |
| JP (1) | JP4423659B2 (en) |
| CN (1) | CN1288489C (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2006138960A (en) * | 2004-11-10 | 2006-06-01 | Nec Corp | Liquid crystal display device and method for manufacturing the same, and projection display device |
| JP2006178235A (en) * | 2004-12-22 | 2006-07-06 | Nec Corp | Thin film transistor array substrate and liquid crystal display device |
| TWI263458B (en) * | 2005-10-25 | 2006-10-01 | Au Optronics Corp | Flat display panel and black matrix thereof |
| US8110832B2 (en) * | 2007-02-22 | 2012-02-07 | Seiko Epson Corporation | Electro-optical substrate, method for designing the same, electro-optical device, and electronic apparatus |
| TWI358832B (en) * | 2007-02-26 | 2012-02-21 | Au Optronics Corp | Semiconductor device and manufacturing method ther |
| KR102067669B1 (en) * | 2012-11-06 | 2020-01-20 | 삼성디스플레이 주식회사 | Thin film transistor array panel and method of manufacturing the same |
| CN103149760B (en) * | 2013-02-19 | 2015-03-11 | 合肥京东方光电科技有限公司 | Thin film transistor array substrate, manufacturing method and display device |
| KR102090518B1 (en) * | 2013-08-30 | 2020-04-16 | 엘지디스플레이 주식회사 | Oxide semiconductor thin film transistor and Display Device and Method of manufacturing the sames |
| CN103746000B (en) * | 2013-12-25 | 2017-03-08 | 深圳市华星光电技术有限公司 | A kind of polysilicon TFT device and its manufacture method |
| CN104022126B (en) * | 2014-05-28 | 2017-04-12 | 京东方科技集团股份有限公司 | Array substrate and manufacturing method thereof, and display apparatus |
| KR102182482B1 (en) * | 2014-07-15 | 2020-11-25 | 엘지디스플레이 주식회사 | OXIDE SEMlCONDUCTOR THIN FILM TRANSISTOR AND ARRAY SUBSTRATE FOR DISPLAY DEVICE HAVING THE SAME |
| US10088727B2 (en) | 2015-10-29 | 2018-10-02 | Seiko Epson Corporation | Liquid crystal device and electronic apparatus |
| KR102469294B1 (en) * | 2016-02-01 | 2022-11-23 | 삼성디스플레이 주식회사 | Organic light emitting display device |
| US10185190B2 (en) * | 2016-05-11 | 2019-01-22 | Semiconductor Energy Laboratory Co., Ltd. | Display device, module, and electronic device |
| CN106773431A (en) * | 2017-04-01 | 2017-05-31 | 京东方科技集团股份有限公司 | Liquid crystal display device structure and preparation method thereof |
| CN108807418A (en) * | 2017-04-28 | 2018-11-13 | 京东方科技集团股份有限公司 | Display base plate and its manufacturing method and display device |
| JP7119564B2 (en) * | 2018-05-17 | 2022-08-17 | セイコーエプソン株式会社 | electro-optical device, electronic equipment |
| US20190355836A1 (en) * | 2018-05-21 | 2019-11-21 | Wuhan China Star Optoelectronics Technology Co., Ltd. | Manufacturing method for amorphous silicon tft substrate |
| JP6702387B2 (en) | 2018-10-08 | 2020-06-03 | セイコーエプソン株式会社 | Electro-optical device, electronic equipment |
| CN112928127B (en) * | 2021-01-12 | 2022-11-04 | 武汉华星光电技术有限公司 | Array substrate |
| CN113327935B (en) * | 2021-05-21 | 2022-07-12 | Tcl华星光电技术有限公司 | Display panel and preparation method thereof |
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| JP4021014B2 (en) | 1997-09-11 | 2007-12-12 | セイコーエプソン株式会社 | Liquid crystal display panel and thin film transistor array substrate |
| JPH11204587A (en) | 1998-01-13 | 1999-07-30 | Furukawa Electric Co Ltd:The | Metal plate with adhesive tape for semiconductor device and manufacture thereof |
| US6542205B2 (en) * | 2000-08-04 | 2003-04-01 | Semiconductor Energy Laboratory Co., Ltd. | Display device |
| JP3460706B2 (en) * | 2000-08-07 | 2003-10-27 | セイコーエプソン株式会社 | Electro-optical device, electronic device, substrate for electro-optical device, and method of manufacturing substrate for electro-optical device. |
| US6583440B2 (en) * | 2000-11-30 | 2003-06-24 | Seiko Epson Corporation | Soi substrate, element substrate, semiconductor device, electro-optical apparatus, electronic equipment, method of manufacturing the soi substrate, method of manufacturing the element substrate, and method of manufacturing the electro-optical apparatus |
| US7027109B2 (en) * | 2001-08-03 | 2006-04-11 | Nec Corporation | TFT array substrate and active-matrix addressing liquid-crystal display device |
-
2003
- 2003-01-31 JP JP2003024473A patent/JP4423659B2/en not_active Expired - Fee Related
- 2003-12-01 US US10/724,040 patent/US7105905B2/en not_active Expired - Lifetime
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Also Published As
| Publication number | Publication date |
|---|---|
| CN1519631A (en) | 2004-08-11 |
| JP2004235557A (en) | 2004-08-19 |
| US20040149989A1 (en) | 2004-08-05 |
| US7105905B2 (en) | 2006-09-12 |
| JP4423659B2 (en) | 2010-03-03 |
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